Contrast-Enhanced Ultrasound in Detection and Follow-Up of an Infrarenal Abdominal Aortic Aneurysm with Aorto-Caval Fistula and Endovascular Treatment

Abstract

An aorto-caval fistula is a rare complication of a symptomatic or ruptured infrarenal aortic aneurysm having a frequency of 3-6%. Patients typically present with clinical signs of diffuse abdominal pain associated with increasing venous congestion and tachycardia, rapid cardiopulmonary decompensation with acute dyspnea, and an audible machinerylike bruit. Perioperative mortality is high, ranging from 20% to 60%. We report a case of an endovascular aortic repair in a patient with a symptomatic infrarenal aortic aneurysm and an aorto-caval fistula. Contrast-enhanced ultrasound seems to be a promising new diagnostic option for the diagnosis and preoperative treatment planning for patients with abdominal aortic aneurysms with rupture into the inferior vena cava. It is in addition to computed tomography angiography. It might allow a more rapid and noninvasive diagnosis, especially for patients in intensive care because of its bedside availability. Because the examination is dynamic, additional information about blood flow between the aorta and inferior cava vein can be evaluated.

Postnephrectomy fistula between the renal artery stump and inferior vena cava treated with Amplatzer vascular plug: Gray‐scale and Doppler sonographic findings

“…6 A recent report suggests contrast-enhanced sonography is a useful technique for adequate demonstration of these fistulae. 7 CT is considered more accurate than sonography in the detection and depiction of their exact topography. 8,9 However, the gold standard technique is catheter angiography, which also enables endovascular or surgical intervention to be planned based on the anatomy.…”

Contrast enhanced ultrasonography versus MR angiography in aortocaval fistula: case report

“…Although the gold standard for detecting and characterizing aortocaval fistula today is CTA [12] and vascular ultrasound is often regarded as a second choice modality, many authors agree that subjects with typical symptoms should not undergo prolonged investigations and that urgent sonography should be the initial diagnostic step [9,13].…”

“…Low-mechanical index technology allows the non destructive stimulation of second-generation sonographic contrast agents while continuously scanning to produce real time contrast enhanced gray-scale images [9,12]. Further the procedure does not require dedicated patient or contrast preparation.…”

“…On the depiction of an abdominal aortic aneurysm by ultrasonography, a following CEUS is recommended to further characterize the abdominal aortic aneurysm and to assess for the possible complication of aortocaval fistula, a situation, which warrants urgent intervention. The bedside examination that is possible with contrast enhanced ultrasound, in particular, for hemodynamically compromised patients having abdominal aortic aneurysm provides a good alternative to MRA or CTA as these modalities have the limitations of crucial time spent for patient transportation and scan acquisition, particularly in the context of an unstable patient, which may interfere with the work of the resuscitative team [12].…”

Aorto-caval fistula from acute rupture of an abdominal aortic aneurysm treated with a hybrid approach

“…5,6 However, in emergency situations this approach is frequently impossible, and it constitutes only a palliative measure in many situations. Most interventional approaches for ruptured abdominal aortic aneurysms have Fig 1.…”